Background: Despite increasing use of infliximab (IFX) in children with Crohn's disease (CD) and ulcerative colitis (UC), long-term durability and safety of IFX beyond 1 year is limited in pediatric inflammatory bowel disease.
Methods: We performed a 10-year single-center retrospective cohort study of 188 patients initiating IFX at <21 years of age with 1-year minimum follow-up. Data were retrieved from medical records. IFX outcomes were defined as sustained remission in the absence of dose modification (sustained durable remission), recaptured response, and treatment failure. Adverse events, anti-infliximab antibodies (ATI), and role of concomitant low-dose oral methotrexate (<10 mg/wk) on IFX durability were analyzed. Univariate associations and survival analysis were performed.
Results: As of the last follow-up, 39% of patients with CD and 29% of patients with UC achieved sustained durable remission and another 60% recaptured and maintained response. For CD, 88% remained on IFX at 1 year, 80% at 2 years, and 82% at 5 years. In UC, 70% avoided colectomy at 1 year. Of IFX failures, 25% with CD and 11% with UC developed ATI. The most common adverse event causing cessation of therapy was infusion reactions. Treatment limiting recurrent infections occurred in <1%, and 1 patient developed lymphoproliferative disease. Low-dose methotrexate did not influence any IFX outcomes.
Conclusions: IFX is safe and effective for long-term maintenance therapy in pediatric patients with inflammatory bowel disease. IFX dose intensification can optimize durability and overcome loss of response. Loss of response is likely affected by development of ATI. Higher doses of oral methotrexate may be needed to optimize IFX.